srl
SNMP
Simple Network Management Protocol (SNMP) is used to monitor and manage devices on a network — routers, switches, firewalls, printers, UPSes, and NAS appliances. It exposes device information through Object Identifiers (OIDs) organised in a Management Information Base (MIB) tree, and it frequently contains logs, configuration, and credentials.
Ports: UDP/161 for agent queries, UDP/162 for traps.
The most common reconnaissance failure is scanning only TCP. SNMP is UDP-only. A TCP-only scan reports the host as having no SNMP service, and the entire attack surface is missed.